Core-knockout device



June 26, 1928.

A. L. \IELSVON Filed June 22, 1925 Patented June 26, 1928.

UNITED STATES PATENT OFFICE.

ADOLPH L. NELSON, or DETROIT, mrcnroan, ASSIGfiOR To BOHN ALUMINUM a BRASS CORPORATION, or DETROIT, mrcnrean.

l OORE-KNOGKOUT DEVICE.

Application filed June 22, 1925. Serial No. 38,913.

The invention relates to molding apparatus and refers more particularly to mold ng apparatus having a core cooperating with the mold. The invention has for its main 6 object the provision of means mounted upon the mold and engageable with a core member cooperating with the mold to loosen the same. Another object is the provision of a knockout device for the core member positioned to engage the core member at its center of percussion to loosen the same. W1tl1 these as well as other objects in View the invention resides in the novel features of construction and combinations and arrangements of parts as more fully hereinafter set forth.

In the drawings 1- Figure 1 is a side elevation of a mold embodying my invention;

Figure 2 is a cross section on the line 2-2 of Figure 1;

Figure 3 is a cross section on the line 33 of Figure 2.

1 and 2 arepermanent sections which together form the permanent mold. A per- 'manent core cooperates with the permanent mold to form the mold cavityo3. This permanent core comprises the side sections {1 and 5 and the center section 6, the side sections having the lateral flanges 7 forming shoulders engageable with the top of the mold section to limit their downward movement andpreferably having a sector shaped cross section below the flanges for engagement with the mold sections. The center section is preferably tapered so that it will move the side sections laterally away from each other into firm contact with the mold sections, the arrangement being such that the side sections will be accurately positioned relative to the mold sections to form therewith a mold cavity having predetermined dimensions.

For the purpose of loosening the side sections 4: and 5 of the permanent core after the metal poured into the mold cavity has cooled sufliciently so that the side sections may be removed from the permanent mold I have provided the knockout pins 8 having the shanks 9 and the heads 10 at the outer ends of the shanks. These shanks are freely longitudinally slidable in the transverse openings 11 formed in the mold sections 1 and 2 and positioned substantially opposite the centers of percussion of the side sections and above the mold cavity.

8 To loosen the side sections of the core its center section is first removed from therebetween and then the heads of the knockout pins aretapped or subjected to light blows suflicient to move the side sections inwardly toward each other after which the side sections may be withdrawn from between the mold sections. In the present instancethe side sections are successively removed owing to the fact that they have at their lower ends the inwardl extending recesses 12 and outwardly exten ing projections 13 therebelow for forming bosses upon the casing, the distance between the bosses of the casing being less than the combined lateral dimensions of the projections 13 but sufficient to allow the removal of one side section at a time.

What I claim as my invention is:

1. The combination with a mold and a core member cooperating therewith, of. means movable in said mold and engageable with said core member to loosen the same.

2. The combination with a mold and a core member cooperatin therewith, of a device mounted upon sai mold and engageable with said core member near its center of percussion to loosen the same.

3. The combination with a permanent mold 'anda permanent core member cooperating therewith, of a pin longitudinally slidablyengaging said mold and engageable with said core member to loosen the same.

4. The combination with complementary mold sections and a core cooperating therewith and comprising side sections, and

means for normally retaining said side sections in operative relation to said mold sections, ofmeans. for loosening said side sections .upon the release of said retalmng means, including members mounted upon section between the same, of longitudinally said mold sections and engageable with said slidable pins mounted upon said mold secside sections to move the same toward each .tions and engageablewith said side sections 10 other. upon removal of said center section to; 5. Ilhe combination with complementary loosen said side sections. mold sections and a core cooperating there- In testimony whereof I afiix my signature. with comprising side sections, and a center ADOLPH L. NELSON. 

